I'm trying to update the styling of the form space page session-expired.htm to bring the styling in line with all the other error pages. I've done this by copy-pasting the Page Content from another error page, and just changing the wording.
The other error pages render their Page Content inside of the Border Template content, but session-expired.htm doesn't seem to do this. It renders just the Page Content html, which of course is missing the Body, Head and all the js and css file references. I'm working around this by including all the missing html into the Page Content for session-expired.htm.
Is there a piece of config I'm missing? How can I get session-expired.htm to utilise Border Template like the other error pages do?